The tool of the present invention is for use on optical fibers. To facilitate the understanding of the invention, an exemplary optical network for delivering high bandwidth communication capabilities to customers is described herein. FIG. 1 illustrates an exemplary network 100. As shown in FIG. 1, the network 100 is a passive network that includes a central office 110 connected to a number of end subscribers 115 and a larger network such as the Internet (not shown). The network 100 includes fiber distribution hubs (FDHs) 130 having one or more optical splitters that generate a number of individual fibers that lead to the premises of an end user 115.
The portion of network 100 that is closest to central office 110 is commonly referred to as the F1 region, where F1 is the “feeder fiber” from the central office. The portion of network 100 that includes a number of end users 115 may be referred to as an F2 portion of network 100. Splitters used in an FDH 130 may accept a feeder cable having a number of fibers and may split incoming fibers into, for example, 216 to 432 individual distribution fibers that may be associated with a like number of end user locations.
The network 100 includes a plurality of breakout locations 125 at which branch cables (e.g., drop cables, stub cables, etc.) are separated out from main cables (e.g., distribution cables). Breakout locations can also be referred to as tap locations or branch locations and branch cables can also be referred to as breakout cables. Branch cables can manually be separated out from a main cable in the field using field splices. As an alternative to manual splicing in the field, pre-terminated cable systems have been developed. Pre-terminated cable systems include factory integrated breakout locations manufactured at predetermined positions along the length of a main cable (e.g., see U.S. Pat. Nos. 4,961,623; 5,125,060; and 5,210,812). Whether manual field splicing or pre-terminated cable systems are used, cutting the entire distribution cable 220 at each breakout location 125 is undesirable. Preferably only the subsets of the total number of fibers are spliced at each breakout location. Optical fiber accessing tools are used to selectively remove protective and insulating layers around the optical fibers to create a fiber access window in an optical fiber cable.
Optical fiber access tools of either the radial slitting or shaver types are typically used to cut a fiber access window in an optical fiber cable. Radial slitters typically include a radially mounted cutting blade for slitting a buffer tube along its length while shaver type tools typically include a cutting blade configured to remove a section of the buffer tube. Exemplary fiber access tools are disclosed in U.S. Pat. No. 4,972,581 to McCollum et al.; U.S. Pat. No. 5,140,751 to Faust; U.S. Pat. No. 5,577,150 to Holder et al.; U.S. Pat. No. 6,023,844 to Hinson, II et al.; U.S. Pat. No. 5,050,302 to Mills; U.S. Pat. No. 4,947,549 to Genovese et al.; U.S. Pat. No. 5,443,536 to Kiritsy et al.; U.S. Pat. No. 5,822,863 to Ott; U.S. Pat. No. 6,581,291 to Tarpill et al.; and U.S. Pat. No. 5,093,992 to Temple, Jr. et al. The tools and methods for accessing optical fibers can be improved. Known fiber access tools are typically difficult to manipulate, especially when the optical fibers to be accessed are tightly wound. In addition, conventional tools tend to bind or chatter, damaging or breaking the buffer tube and the optical fibers contained therein.
The present invention addresses the need in the art for an improved access tool and method for access to a limited number of fibers within an optical fiber cable without causing damage to optical fibers within optical fiber cables.